Image reading apparatus and image forming apparatus

• US 9,432,534 B2
• Filed: 06/25/2015
• Issued: 08/30/2016
• Est. Priority Date: 06/13/2013
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yamamoto, Yuichi, Sakuma, Tomofumi
• Primary Examiner(s): Worku, Negussie
• Application Number:
  US14/750,126
• Publication Number:
  US 20150296093A1
• Time in Patent Office: 432 Days
• Field of Search: 399/262, 399/258, 399/111, 399/119, 399/121, 399/12, 399/13, 399/260, 399/329, 399/333, 399/380, 358/1.15, 358/498, 358/474, 358/488, 358/502, 271/213, 271/220, 271/226, 271/253, 271/9.13, 709/203
• US Class Current: 1/1
• CPC Class Codes: G03G 15/605 Holders for originals or exposure platens for photographic purposes in general G03B
• CPC Class Codes: H04N 1/00554 Latches or hinges therefor
• CPC Class Codes: H04N 1/0057 Conveying sheets before or after scanning arrangements for conveying sheets as part of the scanning operation H04N1/04 and subgroups
• CPC Class Codes: H04N 1/121 Feeding arrangements transporting sheets to or from the scanning position H04N1/0057; control or error compensation of sub-scanning velocity H04N1/0473

Abstract

An image reading apparatus includes: an opening/closing portion configured to be rotatable around a hinge shaft; a biasing portion configured to apply a force to the opening/closing portion such that moment of the hinge shaft rotation higher than moment of the hinge shaft rotation according to self-weight of the opening/closing member is generated in a state in which the opening/closing portion is placed in a range up to a predetermined rotation angle from a closed position with respect to the apparatus main body, and moment of the hinge shaft rotation that is balanced with the moment of the hinge shaft rotation according to the self-weight of the opening/closing portion is generated in a state in which the opening/closing portion is opened more than the predetermined rotation angle; and a holding portion configured to maintain the opening/closing portion at the closed position.

Claims

1. An image reading apparatus comprising:

an apparatus main body including an image reading portion;

a rotating portion configured to be rotatable around a shaft with respect to the apparatus main body, the rotating portion capable of being positioned at a first position, a second position where a rotation angle with respect to the apparatus main body is greater than that at the first position, and a third position where the rotation angle with respect to the apparatus main body is greater than that at the second position;

a holding portion configured to maintain the rotating portion at the first position; and

a biasing portion configured to apply a force to move the rotating portion from the first position to the second position when the maintaining of the rotating portion at the first position by the holding portion is released.

2. The image reading apparatus according to claim 1,

wherein the biasing portion includes a first elastic member and a second elastic member,

wherein the first elastic member applies a force to the rotating portion and the second elastic member does not apply a force to the rotating portion when the rotating portion is positioned in a range from the second position to the third position.

3. The image reading apparatus according to claim 2,

wherein the biasing portion includes an adjustment portion configured to adjust the rotation angle of the second position by changing a position of the second elastic member in an expanding/contracting direction.

4. The image reading apparatus according to claim 1,

wherein the biasing portion includes:

an elastic member configured to apply a force to the rotating portion in an opening direction;

a housing configured to house the elastic member; and

a cam member having first and second cam faces configured to be brought into contact with the housing,

wherein, in a state in which the rotating portion is positioned in a range from the first position to the second position, the housing abuts the first cam face of the cam member so that the rotating portion rotates in the opening direction, and

wherein, in a state in which the rotating portion is positioned in a range from the second position to the third position, the housing abuts the second cam face of the cam member so that the rotating portion stops at a predetermined position.

5. The image reading apparatus according to claim 1,

wherein the holding portion includes:

a magnet that is disposed on one of the apparatus main body and the rotating portion; and

a magnetic body disposed on the other one of the apparatus main body and the rotating portion,

wherein the holding portion maintains the rotating portion at the first position with respect to the apparatus main body using a magnetic coupling force.

6. The image reading apparatus according to claim 1, further comprising:

a supporting portion including the biasing portion and configured to support the rotating portion such that the rotating portion is capable of being positioned at the first position, the second position, and the third position,

wherein the supporting portion supports the rotating portion to be stoppable when the rotating portion is positioned at the third position.

7. The image reading apparatus according to claim 1, wherein, at the first position, the rotating portion closes an original placement portion arranged above the image reading portion.

8. The image reading apparatus according to claim 1, wherein the rotating portion is a sheet feeding device that sends a sheet to the image reading portion.

9. The image reading apparatus according to claim 1, further comprising:

a releasing portion configured to release the rotating portion maintained in the first position by the holding portion.

10. An image reading apparatus comprising:

an apparatus main body including an image reading portion;

a rotating portion configured to be rotatable around a shaft with respect to the apparatus main body, the rotating portion capable of being positioned at a first position, a second position where a rotation angle with respect to the apparatus main body is greater than that at the first position, and a third position where the rotation angle with respect to the apparatus main body is greater than that at the second position;

a holding portion configured to maintain the rotating portion at the first position;

a first biasing portion configured to apply a force to the rotating portion such that the rotating portion is stoppable at a predetermined position, in a state in which the rotating portion is positioned in a range from the second position to the third position; and

a second biasing portion configured to apply a force to move the rotating portion from the first position to the second position when the maintaining of the rotating portion at the first position by the holding portion is released.

11. The image reading apparatus according to claim 10, further comprising an adjustment portion configured to adjust the predetermined rotation angle by changing a position of the second biasing portion in an expanding/contracting direction.

12. The image reading apparatus according to claim 10,

wherein the holding portion includes:

a magnet that is disposed on one of the apparatus main body and the rotating portion; and

a magnetic body disposed on the other one of the apparatus main body and the rotating portion,

wherein the holding portion maintains the rotating portion at the first position with respect to the apparatus main body using a magnetic coupling force.

13. The image reading apparatus according to claim 10, further comprising:

a supporting portion configured to support the rotating portion such that the rotating portion is capable of being positioned at the first position, the second position, and the third position,

wherein the supporting portion supports the rotating portion to be stoppable when the rotating portion is positioned at the third position.

14. The image reading apparatus according to claim 10, wherein, at the first position, the rotating portion closes an original placement portion arranged above the image reading portion.

15. The image reading apparatus according to claim 10, wherein the rotating portion is a sheet feeding device that sends a sheet to the image reading portion.

16. The image reading apparatus according to claim 10, further comprising:

a releasing portion configured to release the rotating portion maintained in the first position by the holding portion.

17. An image forming apparatus comprising:

an image forming portion configured to form an image on a recording medium;

an apparatus main body including an image reading portion;

a rotating portion configured to be rotatable around a shaft with respect to the apparatus main body, the rotating portion capable of being positioned at a first position, a second position where a rotation angle with respect to the apparatus main body is greater than that at the first position, and a third position where the rotation angle with respect to the apparatus main body is greater than that at the second position;

a holding portion configured to maintain the rotating portion at the first position; and

a biasing portion configured to apply a force to move the rotating portion from the first position to the second position when the maintaining of the rotating portion at the first position by the holding portion is released.

18. An image forming apparatus comprising:

an image forming portion configured to form an image on a recording medium;

an apparatus main body including an image reading portion;

a rotating portion configured to be rotatable around a shaft with respect to the apparatus main body, the rotating portion capable of being positioned at a first position, a second position where a rotation angle with respect to the apparatus main body is greater than that at the first position, and a third position where the rotation angle with respect to the apparatus main body is greater than that at the second position;

a holding portion configured to maintain the rotating portion at the first position;

a first biasing portion configured to apply a force to the rotating portion such that the rotating portion is stoppable at a predetermined position, in a state in which the rotating portion is placed in a range from the second position to the third position; and

a second biasing portion configured to apply a force to move the rotating portion from the first position to the second position when the maintaining of the rotating portion at the first position by the holding portion is released.